The structure located in the backyard of a property went up in flames Sunday. Fire investigators combed the building at that time, but the body was discovered Tuesday.
"Shortly before noon this afternoon there was a private arson investigator that was on the scene as a result of a follow-up for the fire that occurred on July 31. When he was back there doing his investigation, he discovered the deceased," said Lt. Tracey Ibarra of the Pasadena Police Department.
The property owners who have live in the main house for 25 years say they're upset by the gruesome discovery. They said they have no idea who the victim may be.
"They did not have any renters," Ibarra said. "In the past we heard that they had rented to someone, but that individual has been contacted, they are unharmed and not connected with this case at all."
Neighbor Robert Cameron's yard backs up against the rental structure. He called 911 when he saw the flames.
"All of a sudden I saw 20-, 30-foot flames in a tree in the back," he said. "I looked in the back over the fence and the fire had jumped to the garage. I said 'Wow, this is getting big.' Three or four hours later, incredible. I didn't think anybody would pass away."
An autopsy is scheduled to determine the cause of death and find out more details about the victim.